title: Exosome encased spherical nucleic acid gold nanoparticle conjugates as potent microRNA regulation agents.
abstract: Exosomes are a class of naturally occurring nanomaterials that play crucial roles in the protection and transport of endogenous macromolecules, such as microRNA and mRNA, over long distances. Intense effort is underway to exploit the use of exosomes to deliver synthetic therapeutics. Herein, transmission electron microscopy is used to show that when spherical nucleic acid (SNA) constructs are endocytosed into PC-3 prostate cancer cells, a small fraction of them (<1%) can be naturally sorted into exosomes. The exosome-encased SNAs are secreted into the extracellular environment from which they can be isolated and selectively re-introduced into the cell type from which they were derived. In the context of anti-miR21 experiments, the exosome-encased SNAs knockdown miR-21 target by approximately 50%. Similar knockdown of miR-21 by free SNAs requires a ≈3000-fold higher concentration.
authors.affiliation: Department of Chemistry and International, Institute for Nanotechnology, Northwestern University, 2145 Sheridan Road, Evanston, IL, 60208-3113, USA; Interdepartmental Biological Sciences Program, Northwestern University, 2205 Tech Drive, Evanston, IL, 60208-3113, USA.
authors.forename: Ali H
authors.initials: AH
authors.lastname: Alhasan
authors.forename: Pinal C
authors.initials: PC
authors.lastname: Patel
authors.forename: Chung Hang J
authors.initials: CH
authors.lastname: Choi
authors.forename: Chad A
authors.initials: CA
authors.lastname: Mirkin
mesh_terms: D045744:Cell Line, Tumor; D055354:Exosomes / Q000737:chemistry*; D006046:Gold / Q000737:chemistry*; D006801:Humans; D053768:Metal Nanoparticles / Q000737:chemistry*; D035683:MicroRNAs / Q000235:genetics*
chemical_list: D035683:MicroRNAs; D006046:Gold
keywords: cancer therapy; exosomes; gene regulation; gold nanoparticles; microRNA